We have never begun the pool season with a pool that looks this bad. Due to unfortunate circumstances, we were not able to cover the pool last fall. While I've been working for two days to remove all debris, I'm a little hesitant to just start shocking as I usually do. I have filled up with water and been running the filter for about 24 hours. The water is brownish green, has visible algae growth on the sides, and I can only see about 3 inches below the surface. Any suggestions with where to begin? Many thanks!